The use of lipase in laundry detergent formulations to remove oily soils is well known in the art. U.S. Pat. No. 5,223,169 to El-Sayed et al describes the use of hydrolase enzymes including lipases for laundry applications. U.S. Pat. No. 5,069,810 to Holmes et al is directed to detergent compositions comprising microbial lipase and dodecylbenzene sulfonate.
Soil release polymers, and in particular, those commonly referred to as PET-POET copolymers (polyethylene terephthalate-polyoxyethylene terephthalate) have been widely suggested as components of detergent compositions. U.S. Pat. Nos. 4,569,772 and 4,571,303 to Ciallella describe nonionic detergent compositions containing stabilized PET-POET copolymers as soil release agents. Enzymes such as proteolytic and amylolytic enzymes are listed among the optional adjuvants.
U.S. Pat. No. 5,026,400 to Holland et al describes compositions containing narrow range ethoxylate nonionic detergents in combination with PET-POET copolymers and builders.
While detergent compositions containing soil release polymers have proven to be commercially successful as laundry compositions, the effective removal of oily stains from a variety of fabrics remains as a persistent problem area which commercial liquid and granular laundry formulations seek to address.